Iptables newbie / simple question
 

Ok, i am trying to come up with a iptables setup.....just started looking around today..have a extremely simple question on a concept..by the way this is for a dial up connection..

iptables -A INPUT -s localhost -p icmp -j ACCEPT
iptables -A INPUT -p icmp -j DROP


ok, lol...this is how far i got so far, blocking icmp.. (me being able to ping myself is pointless i know, but just trying to figure how once a rule applies to let it thru) it goes to first rule, then moves to next....but then it will get dropped....so how do i make it so once it gets accepted not to move on??? or even better yet does someone have a good recent tutorial or something to point me in the right direction....thanks


EDIT: ok, i guess by me adding a.......
iptables -F ....at the beginning it works out, so once a something matches thats it, it stops going??? also a good tutorial would still be nice -thanks

there are many a good tutorial out there to look at man...

I think you need to understand what is meant by a "default policy"...

you should be running a "DROP" by default policy... then you only make rules for connections you want to come into the box.... everything else gets dropped...

I would check out the FAQ post listed at the top of this forum as a start... then if you are serious about learning linux firewalls (and more specifically, iptables) I would pick up Robert Ziegler's book "Linus Firewalls". I have found it to be a great reference/asset.

One thing you will need to look into is masquerading since you are firewalling a dial-up connection...

GL yo... :D

and use the search function... you'll find some good stuff in here...